1. Applicable Field of the Invention
This invention relates to a coating stripper to be suitably used for terminating a coated optical fiber for connection with another optical fiber or equipment.
2. Prior Art
A connecting means called an optical connector is popularly used for connecting an optical fiber with another optical fiber and/or with equipment. A so-called fusion connector that utilizes discharge heat is widely used for interconnection of optical fibers.
In any case, be it a single core plastic-coated optical fiber or a multiple plastic-coated optical fiber, the coating of the optical fiber should be removed from an end thereof to expose the optical fiber of that area.
To remove the coating layer of an optical fiber having a coating layer formed on the outer periphery of the optical fiber at an end thereof, a pair of juxtaposed edges of a cutter are arranged transverse to the axis of the coated optical fiber and so moved that they cut into the coating layer. Thereafter, the coated optical fiber and/or the cutter are subjected to a tensile force applied in a direction suitable for effecting separation of the coating layer and the optical fiber (axial direction of the coated optical fiber).
With such an operation, the coating layer comes to have a crack at and around the spots where it is cut by the edges and consequently the coating layer of the end area can be removed from the optical fiber.
When the coating layer of a coated optical fiber is relatively loosely fitted to the optical fiber, an end portion of the coating layer may be easily and neatly removed from the optical fiber by simply holding the edges of the cutter under a condition where the edges cut into the coating layer but are separated from each other by an appropriate distance.
When, on the contrary, the coating layer of a coated optical fiber is firmly fitted to the optical fiber, a heater may also be used to heat and soften the coating layer along with a cutter that physically breaks the layer.
As the coating layer is softened by heat, the affinity between the optical fiber and the coating layer is reduced so that they may be separated from each other with ease.
FIG. 3 of the accompanying drawings illustrates a coating stripper for optical fibers, known in the art, as described above.
In FIG. 3, the coating stripper comprises a pair of clamp members 1A, 1B having matching surfaces 2a, 2b respectively provided with cutting edges 3a, 3b and coating holding members 4a, 4b, said clamp members 1A, 1B being connected with each other by means of a hinge 5 so that the pair of cutting edges 3a, 3b as well as the pair coating holding members 4a, 4b may be swingable relative to each other. Moreover, a heater 6 is embedded in the clamp member 1A.
Covered optical fiber 11 of FIG. 3 comprises a quartz type optical fiber 12 and plastic coating layers 13, 14 formed around the outer periphery of the optical fiber 12.
It should be noted that the coating layer 13 constitutes an internal coating layer and the coating layer 14 constitutes an external coating layer of the optical fiber 12 when the coated optical fiber 11 is a single core coated optical fiber, whereas, if the coated optical fiber 11 is a coated multifiber as illustrated in FIG. 4, the coating layer 13 represents a coating layer for each single core optical fiber and the coating layer 14 represents a coating layer that coats all the optical fibers that constitute the coated multifiber.
Referring to FIG. 3 once again, when the coating layers 13, 14 are removed at an end area of the coated optical fiber 11, firstly the clamp member 1B is rotationally moved in the direction as indicated by arrow I in order to separate the pair of coating cutting edges 3a, 3b from each other as well as the coating holding members 4a, 4b. Then the coated optical fiber 11 is placed on the coating cutting edge 3a and the coating holding member 4a of the clamp member 1A at an end area of the coating and thereafter the clamp member 1B is moved back in the direction as indicated by arrow II to close the pair of coating cutting edges 3a, 3b as well as the pair of coating holding members 4a, 4b. At the same time the end area of the coating layer 13 and that of the layer 14 are heated by the heater 6.
Now, the end area of the coated optical fiber 11 is clamped by the pair of coating holding members 4a, 4b and the coating layers 13, 14 are cut by the pair of coating cutting edges 3a, 3b.
If the coated optical fiber 11 is pulled in the direction as indicated by arrow III under this condition, the coating layers 13, 14 are split along the cutting lines of the coating cutting edges 3a, 3b and the core optical fiber 12 is pulled away from the portion of the coating layers separated and retained by the coating holding members 4a, 4b of the respective clamp members 1A, 1B.